Certain types of semiconductor packages are fabricated in pre-determined arrays on a substrate, preferably a polyimide tape or film and wherein the packages are encapsulated by an elastomer sealant also deposited on the tape or film. The arrays of semiconductor packages, including the polyimide tape or film substrate structure is secured to a metal frame having a central opening therein such that the packages may be subjected to a cutting operation to cut through the polyimide tape and also through the elastomer sealant layer. Typically, the operation is conducted in two cutting steps at two different stations to completely separate each semiconductor package from the substrate.
The aforementioned prior art method of separating semiconductor packages, particularly micro ball grid arrays (.mu.BGAs), often introduces errors in the cutting operation due to misalignment of the packages when moved from one cutting station to the next. This action produces slivers or partially cut portions of the package supporting substrate along one or more edges thereof, resulting in costly rework or modification of the packages before they can be further processed. The present invention overcomes the problems associated with prior art cutting methods for separating semiconductor packages from their support structure, as will be described further herein.